摘要
通过大量文献调研，概述注CO2提高气藏采收率（EGR）。注CO2提高气藏采收率的主要方法，是剩余天然气恢复压力法——将CO2高压注入地层并恢复地层压力。在地层条件下，CO2一般处于超临界状态，粘度大大高于甲烷粘度，密度远大于甲烷。随着注入量的增加，使CO2向下运移可稳定地将甲烷驱替出采出井，并具有避免沉淀和水侵发生的优点。文献表明，CO2纯度与注入气体扩散系数成反比，扩散系数小，天然气采收率高，CO2含量为99．433％的注烟道气可提高采收率至88％-90％OGIP，效果最佳。CO2扩散系数、在水中的溶解性、注入时间及注入速率对提高采收率均有不同程度的影响。
By survey of plenty of literatures, CO_2 injection to improve recovery factor of gas reservoirs is introduced. The main method of CO_2 injection to improve recovery factor of gas reservoirs is the one of building up the residual gas pressure, i.e. CO_2 with high pressure is injected into the reservoir to build up the reservoir pressure. Under the conditions of reservoirs, CO_2 is usually in the super-critical state. Its viscosity is much higher than that of methane and its density is much more than that of methane. As the injection volume increases, CO_2 will move toward down to drive the methane to producing wells. The method can eliminate sediments and water-invasion. The literatures show the CO_2 purity is in inverse ratio with the diffusion coefficient of the injected gas. The smaller the diffusion coefficient is, the higher the recovery factor of gas is. It can increase the recovery factor by 88~90% of the original gas in place (OGIP) to inject the flue gas , of which CO_2 content reaches 99.433%. That is the best way. The diffusion coefficient, the solubility in water, the injection time and velocity of CO_2 have different influences on the improvement of recovery factor.
出处
《天然气勘探与开发》
2006年第3期40-41,50,共3页
Natural Gas Exploration and Development
关键词
提高
气藏采收率
恢复压力
驱替
烟道气
扩散系数
improvement, recovery factor of gas reservoirs. pressure building up, driving, flue gas, diffusion coefficient.
作者简介
胥洪俊，男，1981年生于四川隆昌；现为在读硕士研究生，主要从事注气提高采收率、油气藏及相态分析研究。地址：（610500）四川成都新都区西南石油大学硕2004级1班。电话：13551830833。E-mail：xuhongiuntim@sina．com
